
; assume cs:code
; code segment

; start:  mov al,2        
;         out 70h,al      
;         mov al,0        
;         out 71h,al      
;         mov ax,4c00h
;         int 21h

; code ends
; end start

assume cs:code
code segment

start:  mov bx,ax
        shl ax,1   
        mov cl,3
        shl bx,cl      
        add ax,bx      
        mov ax,4c00h
        int 21h

code ends
end start